Mechanical trip for excavators



P. E" BUTCHER. MECHANICALIRIP FOR EXCAVATORS.

APPLICATION FILED FEB- 16, 19]7.

Patented 00a 26,1920.

NITE STATES PATENT omen.

PIERPONI E. m ronnn, OF'MILWAUKEE, wrs'cousm.

MECHANICAL TRIP FOR EXCAVATORS.

Application filed February 16, 1917..

To all w ho'm it may concern:

Be it known that I, PIERPONTE.D UTGHER, a citizen of the United States of America, and a resident of Milwaukee, Milwaukee county, WVisconsin, have invented a certain new and useful Improvement in Mechanical Trips for Excavators, of which the following is a specification.

My invention relates particularly to excavators of the types known as dipper dredges or steam shovels, where the bucket or dipper that does the excavating is carried by'a handle which is mounted upon a boom. The handle and boom are so mounted and connected that the dipper may be raised and lowered and swung from side to side so that the dipper can assume a variety of positions, and in operation is caused to dig through an arc of approximately ninety degrees in a vertical plane and is then swung over a car, wagon, scow, or other receptacle and its loaded material dumped therein.

The dipper as customarily built has abottom or door plate hinged thereto and held in position by a latch during the digging cycle. After this is complete, and it is desired to dump the excavated material, the latch is tripped, the door plate opens and the material is dumped. Various methods have been proposed for operating the latch or trip. In small machines it is done manually either by a hand line attached to the latch or through the intervention of simple or compound levers. In large machines this is impractical because the great weight of the material on the latch "causes excessive friction and'in large machines various types of power driven trips have been used. The difficulty in the past has been to get a power driven trip that could be mounted in a place that is 'operatively unaffected by the motion of the handle or boom, is out of the way ofthe gears, machinery, hoist chain, and other moving parts, that can be applied to any type of dipper dredge without the necessity of special gear ratios, special size winding drums, etc., and is entirely independent of the shovel operating mechanism. 1 know of no such device that has heretofore been patented, described, or used, and my invention designs to affect these improvements and to give in addition to safe mounting for the operating mechanism, practically a straight lead for the trip line from the dipper latch along the dipper handle and above it and the boom,-thus' clearing all of the Specification of Letters Patent.

Serial No. 149,030.

mechanism and being in a place that is least exposed to accident and wear. In addition it may be applied to any dredge or shovel and needsno special gear rat os, drums, or other mechanism and is entirely independent of the operating mechanism.

To this and other useful ends my invention consists in the mechanism hereinafter set forth and claimed. In the accompany- Pat nted Oct. 26, 1920.

type of dipper.

ing drawings Figure 1 is a side elevation of a power operated dipper dredge embodying the principles of my invention. Fig. 2 is a sectional view of the same taken along the line 2-2 in Fig. 1 looking in the direction of the arrows. Figs. 1 and 2 show a steam operated device.

As it is illustrated the excavator isof the well known form in' which the boom. 1 (made in two parts) is rotably mounted on the pivot 52 by means of ropes or chains attached to a swing circle 3, and the handle l'is attached to the boom 1 by means of a rack 5 and a pinionfi which is operated by means of a thrust gear 7 whichmay be driven by steam engine, electric motor, or other suitable machinery-not shown in the drawing. The dipper 8 having the hinged door plate 9 held by the latch 10 is sup-' ported by the pulley 11 over which'and the fixed sheaves 12 passes a hoist rope or chain 13 which is operated from a drum driven by steam engine, electric "motor, or other sultable machinery not shown in the drawmg The handle 4 isgenerally made in two parts as is shown, particularly in the cross section Fig. 2, but is held in position by being slidably mounted in a saddle block 15'; comprising. a vertical portion 16 and a slide plate 17. The saddle block 15 is sometimes mounted so that the verticle portions thereof straddle the" handle 4 or the parts thereof. All of the device so far described is old and well known.

In one form of my device I mount upon the slide plate 17 of the saddle block 15 the steam cylinder 18 so that the piston 18' therein will move upward when steam is admitted to the cylinder. The mounting is similar where the saddle block straddles the on the outside of the boom. In that event it is generally more convenient to mount the steam cylinder 18 upon the side of the saddle block. On the end of the piston 18' is a pulley or sheave 19 and on both ends of handle, as in cases where the handle passes the slide plate 17 are two fixed pulleys or sheaves 20. I lead the trip line 23 from the latch 10 over sheave or sheaves 21 which are mounted between the two portionsof the handle; under the fixed sheave 20, over the movable sheave 19, under the. other fixed sheave 20, and attach the ,end thereof to the end of the handle 4 as shown at 22. I may, at my option, omit ,the sheave or sheaves 21 and sometimes carry the trip line 23 on the outside of the handle 4: instead of between the two parts thereof. By so .attaching the end of the trip line 23 it is a fixed quantity with relation to the motion of the dipper and dipper handle and as the same move backward and forward by means of the rack 5 and the pinion 6 there is'no change in the length of the trip line 23. If desired a handoperated trip lever 24 may be interposed in the trip line 23 and an end line 25 attached thereto.

In operation the latch 10 is tripped by applying steam, air, water or fluid generally to the trip mechanism which results -in raising the movable sheave 19, which puts a strain on the trip line 23 causing it to trip the latch 10 and open the door plate 9.

In practice I generally use steamin preference to any other fluid and the steam cylinder is attached to the steam supply by means of a flexible connection or hose 32.

It will be seen that this means of mounting the trip mechanism and of leadin the trip line permits the trip line to be a xed to the handle and that there is no necessity of attaching it to any portion of the mecha-- nism which moves relatively thereto, it being merely led over sheaves on the slide plate.

The lead is straight, is above the handle and out of the way of material to be excavated and of the operating machinery, whereas the mechanism for operating the trip is fixed at a convenient place, is independent of the hoist rope. or chain, and ot' the machinery for operating the dipper. This results in a mechanism which is simple, compact, placed in an unexposed position, and is positive in operation.

I can if desired operate any mechanism.

that may be desired to be mounted on the handle or bucket other than a distinctive mechanical trip, and I do not want to be understood as limiting my invention to a means'of operating a mechanical trip except in those claims wherein it is distinctly claimed.

Having fully described my invention, I claim:

1. In a dipper dredge excavator having a saddle block, and a dipper handle slidably mounted thereon, the combination of a.

mechanism attached to the dipper handle,

andmeans for operating said mechanism mounted on the saddle block, said operating means being unafiected by the motion of the affixed at .or near the free end of the dipper handle, and means for operating said trip line mounted upon the saddle block, said operating means being unaffected by the position of the dipper handle.

4. A mechanically operated trip for use on dipper dredge excavating machinery having a saddle block, comprising a trip line afiixed to the latch to be tripped, and afiixed at or near the free end of the dipper handle, and passing over the sheaves hereinafter mentioned and a movable sheave actuated by suitable machinery for tripping the latch said machinery being mounted on the saddle block.

5. A mechanically'operated trip for use on dipper dredge excavating machinery having a saddle block, comprising a trip line afiixed to the latch to be tripped and aflixed at or near the free end of the dipper handle, and passing over the sheaves hereinafter mentioned, fixed sheaves mounted on the saddle block, a movable sheave adapted to be actuated by a fluid cylinder and piston, said cylinder and piston being mounted upon the saddle block.

6. Means for operating mechanism attached to or near the bucket of a dipper dredge excavating machine using a saddle block,-comprising a line afiixed'to the mechanism to be operated and also afiixed at or near the end of the dipperhandle, and pass PIERPONTJE. BUTCHER.

Witnesses:

F. J. GooDRIoH, H. B. GoonRIoH. 

